1. Field of the Invention
The present invention relates to a pallet exchange apparatus for exchanging pallets between a table of a machine and turntable at a loading and unloading station.
2. Discussion of the Background
Pallet exchange apparatuses are known having a turntable at a loading and unloading station which is indexable to predetermined rotational positions to make it easy for an operator to load and unload a workpiece from a pallet mounted on the turntable, and an exchange mechanism for exchanging pallets between the turntable and a table of a machine tool.
In such pallet exchange apparatus, it is necessary to engage the pallet with the turntable and to disengage the same from the exchange mechanism during loading and unloading operation by the operator. In addition, it is necessary to engage the pallet with the exchange mechanism and to disengage the same from the turntable during the exchanging operation by the exchange mechanism.
Conventionally, such a pallet exchange apparatus is provided with pins which are slidably mounted on the turntable and which are moved by an actuator to engage with and be disengaged from the pallet, and a plurality of latches are pivotally mounted on the exchange mechanism and are rotated by an activator so as to engage with and be disengaged from the pallet.
Moreover, such conventional pallet exchange apparatus is operatively associated with a machine tool in such a manner as to place the pallet exchange apparatus in a desired approximate position relative to the machine tool followed by adjusting precisely the position of the exchange mechanism relative to the table of the machine tool, and finally, adjusting exactly the position of the turntable relative to the exchange mechanism.
As a result, such conventional pallet exchange apparatus becomes comparatively complex and large in structure as well as expensive. In addition, skill and time to adjust positions of the exchange mechanism and the turntable are required.